The present invention relates to a lifting device and more particularly to a lifting device which is adapted to load and unload loads from a truck utilizing a minimum of the length of a truck bed.
Lifting devices for trucks such as pickup trucks are well known and one particular device is disclosed in U.S. Pat. No. 3,276,610 granted on Oct. 4, 1966 to C. R. Thatcher. In this device booms are carried on the rear of a pickup truck for lifting loads into and from the pickup truck. One problem with such devices is that the load travels along the same arcuate path as it is lifted from the ground onto the truck. In some particular cases this presents a problem in that the bed of the truck has to be of sufficient length so that the load does not strike the rear portion of the cab of the truck as such is being deposited therein.
In U.S. Pat. No. 3,170,580 granted on Feb. 23, 1965 to V. G. Soyko such would not be the problem since the boom is telescoping. By varying the length of the boom as the load is placed into the truck such would enable the arcuate path that the load travels as it is being placed in the truck to be varied.
Other standard loading devices for trucks are illustrated in U.S. Pat. No. 2,848,123 granted on Aug. 19, 1958 to C. R. Keyes and U.S. Pat. No. 2,099,998 granted to R. H. Byrd granted on Nov. 23, 1937.